@Garouchomp There's two problems with it:
One - it takes a LOT of effort to really, truly master a technique. Having a whole lot of techniques that you took from elsewhere, developing them to be "good enough", and switching them out on a whim is a mindset with a lot of similarities to cowardice; you don't have the spine to make something of yourself, so you mimic the flashy bits of someone else's work and falsely call yourself their equal or better. The trust-fund-baby mentality applied to martial arts, if that makes any sense. Any devoted martial artist is going to hold such a coward in contempt.
Two - If you haven't actually mastered a technique, then it is fragile. Maybe it gets results, but it's easy to disrupt; not something you can really rely on when the chips are down. Like Mike Tyson says: "Everyone has a plan until they get punched in the face." A technique is only really "good" after you've practiced it to the point where muscle memory will do it for you even after your brain shuts down.